Neutron detection efficiency and capture product energy spectra of all-semiconducting-boron carbide and conversion-layer detectors

Solid-state neutron detectors based only on boron-rich semiconductor are of interest for their potential to provide the highest thermal neutron detection efficiencies of any solid-state neutron detectors. A simplified physical model is shown to generate capture product spectra that agree quantitatively with full-physics GEANT4 simulation. Using this model, comparisons are made between the ideal capture-product energy spectra of planar conversion layer and all-boron-carbide-semiconductor detectors. The energy distributions and efficiencies of the ideal all-boron-carbide-semiconductor are found to be highly advantageous, with thermal neutron detection efficiencies potentially of 50 to 80% for devices only 20 to 50 μm thick.